This reminds me of an article I read on osopinions about a week ago. While the ostensible focus of the article was KDE, it applies to the question you pose.
The gist of the article was that not only was it bad to theme your computer interface, it was bad for the system to even allow the possibility.
The author was yet another of those 'human interface experts' with the concomitant 'one size should fit all' philosophy.
I agree with the principle that the basal system should conform to a consistent set of rules and conventions, but the idea that you should not be able to modify the interface to suit what works best for you (practically or aesthetically) smacks a bit much of arrogance, the idea that 'we know what's best for you ... now shut up'.
I guess the average user just doesn't really think about their computer, beyond having to use it. I have my PC at work fairly completely customized (and it changes pretty frequently), and while they comment about it favorably, they still show no interest in doing so themselves. I have managed to get a couple of people interested in customization, but it does seem that a large number of people really don't care. And some of them are as proficient as I am at using computers, and spend about as much time on them as well. I do occasionally get some comments about how I'm probably wasting time with customizing even after I demonstrate how it makes me more productive.
Some people appear to be hopelessly utilitarian. I'm glad there are a large number of us with the desire (and the tools) to give us the option. It's worth it
